Albert blauvelt



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DIFFERENTIAL MECHANISM. No. 548,350.

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Patented Oct. 22, 18,95.

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A'.BLAUVELT. DIFFERENTIAL MECHANISM.

No. 548,350. Patented Oct. 22, 1 95.

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' UNITED STATES PATENT. OFFICE,

ALBERT BLAUVELT, OF YORK, N. Y.

DIFFERENTIAL; M ECHANISM.

SPECIFICATION forming part of Letters Patent No. 548,350, dated October 22, 1895. Application filed June 6, 1890. 3 Serial N0. 354,455- (No model.)

To all whom it may concern:

Be it known that I, ALBERT BLAUVELT, a citizen of the United States, residing in the city, county, and State of New York, have i115 vented certain new and useful Improvementsin Differential Mechanism, of which the fol-. lowing is a specification sufficient to enableothers skilled in the art to which the invention appertains to make and use the same.

My improvements relate to mechanism for effecting a difference in the relative speed of rotation between two parts revolving together in the same direction around a common axis; and the invention consists, essentially, in the use of a stationary worm, together with a worm-gear and suitable auxiliary gearing interposed between the two rotating parts.

In the accompanying drawings I illustrate means for giving practical effect to my improvements, although I do not wish to confine myself to the identical form and construction of parts shown, since it is obvious that various modifications may be introduced without departing materially from the essential features of my invention.

Figure 1 is a sectional elevation of one form of my differential mechanism; Fig. 2, a plan of the same. Fig. 3 is a sectional elevation upon plane of line 00 as, Fig. 2. Fig. 4 is asectional' elevation of a modified form of the mechanism, and Fig. 5 is a similar view taken at right angles to Fig. 4.

As shown in the accompanying drawings, the apparatus is arranged upon and between a vertical shaft A and a sleeve 13, both the shaft A and the sleeve rotating together in the same direction, but at slightly difierent The shaft A and sleeve B are supported in position by suitable bearings or other wellknown means, according to the requirements of the particular use to which the mechanism is to be applied. For the purpose of illustra tion the drawings show the sleeve B and shaft A as steadied in position vertically by a bearing 0, the secured rigidly to a cross-timber D.

The bed-plate G of the differential train of gearing G is secured to the upper extremity of the shaft A, while the large gear g of said train is secured to the upper end of the sleeve B. A vertical counter-shaft g is mounted in the frame G, its lower end carrying the pinion g and its upper end the beveled gear g ,which latter meshes with a beveled pinion 9 attached to one end of a horizontal shaft 9 to the other extremity of which a worm-gear g is secured. The gears g g are counterbalanced by the weight b.

The rotation of the shaft A and the sleeve B is efiected by any suitable mechanism, power being applied to either one orthe other, as may be required, by pulley, gear, or other well-known means. They are coupled to gether by the differential mechanism, and would rotate together in the same direction and at the same rate of speed were it not for the worm c, which engages with the wormgear 9 This worm c is suspended upon a rod (1, secured to a stationary support in such manner that while it cannot rotate upon its own axis it is free to adapt itself to the motion of the parts below. The worm is steadied by a bracket (1, projecting upward from the frame G, and its lower end 0 is stepped in the upper end of the shaft A, the worm being held practically rigid and stationary and acting as a fulcrum against which the wormgear 9 acts to effect the differentiation in motion.

The engagement of the worm c with the worm-gear g aifords sufficient resistance to the rotation of the train of gearing, 850., with the shaft A to compel the worm-gearg to rotate upon its own axis,the worm c acting as a stationary fulcrum to efiect the change in the relative rates of speed between the sleeve B and the shaft A. The large gear g would have no effect on the pinion g and its connection were it not for the resistance afforded the worm'o', since the whole train G, frame G, and all, would otherwise be carried around with the shaft A without efiecting an independent movement of the gears composing the train G. The worm 0', however, tends to for giving a gain or loss of one turn t0,say,=

seven hundred of the draining-cylinder.

My reasons for inventing and using a dif ferential gearing such as'shown in 'thedrawings are of a purely mechanical sort. :By

way of illustration take, for instance, its use. in connection with centrifugalapparatus. In such case it is necessarytto avoid clogging.) to use a conveyer or screw in the centrifugal; of not much less than six inches pitch, pref-' The material being opera'tedf on usually requires to remain for several; minutes in the machine-say, for example, It, therefore, the conveyen screw revolves within the strainer once a minute it will move the material through sixj inches perminute and in five minutes two:

erably more.

five minutes.

and one-half feet, which is as much as is a convenient depth of strainer fora single machine, and in turn is more than is convenient to allow for the progress of material. during one operation in a double or treble. centrifugal. The material beingoperatedon is thrown out against the walls of themachine and presses radially against the same with af force depending on the velocityvof rotation,

whichin ordinary work is sufficient to make it difficult to move the material downward along the annular wall of the strainer. Ina machine of the ordinary size of sugar-centrifugals a force of at least a thousand pounds would be required to move a mass of material downward within the strainer-cylinder when running at speed.

From the foregoing it will be seen thatthe motion required to be imparted to the screw within the strainer-cylinder must be-slow, in the neighborhood of once a minute,and must be powerful to positively and evenly screw thematerial downward and properly feed the machine. The rotativespeed of the entire machine is, however, very rapid and may be taken, for example, at two thousand revolutions per minute. Suppose the problem is to derive a motion from a speed of two thousand revolutions per minute and convert it into a positive even, correlative, but slow and powerful movement of one turn per minute. Obviously no speeds derived from disconnected sources of power can be regulated to such fractional-n icety. If belts were employed for this purpose it'would be necessary to employ two belts, driven exactly at the same speed, and to have aopulley to the shaft carrying the strainer and another to the screw within the same. Oneof thesepulleys could be aslarge as fortyinchesin diameter for an extreme; the other would have to be one two-thousandths or-one-fiftieth inch less in diameter. As is well known, all belts creep, and this creep varies with the load on the belt, and amounts to more than one two-thonsandths of the speed of a'belt when carrying a due load. Therefore the natural irregularity of transmission of speed by belting is an amount exceeding the amount of difference of speeds necessary for our purpose.

Additional to the above a wide and continuous'belt would be required in any case to transmit the strain due to the slow torsion and heavy resistance of the screw, as hereinbefore setforth.

gitudinal axis substantially in the manner and for the purpose described.

ALBERT BLAUVELT. Witnesses:

IRVING Cox, P. M. WASHABAUGH. 

